Patent GB-421886-A (GB)
Title: Improvements in and relating to door locks, night latches and the like
IPC: E05B55/00
Filed: 1933-05-02
Abstract: 421,886. Lock &c. cases; night-latches. WILDER, J. R., 149, Compton Road, and RAMSELL, H. G., Alverley, York Gardens, both in Wolverhampton. May 2, 1933, No. 12803. [Class 44] The case of a night-latch or other latch or lock is let into the face of the door in a recess which extends to the edge of the door, and the front plate is dished to provide a flange on three sides seating against the face of the door. The front plate may form a separate cover-plate to the case proper, or may be integral with the sides of the case, which then has a removable back plate. The flange may have holes for passage of attachment screws, or, when the front plate is separate it may serve to hide the attachment screws. The case is particularly described in combination with a cylinder lock as in a night-latch. The cover-plate may have upward and downward extensions to serve as finger plates. As shown in Fig. 2, the flange 2 of the dished cover-plate 1 seats against the face of the door 4 and the case 8 containing the latch mechanism is let into a recess 11 in the face of the door and extending to its edge 12, which has a slight recess to receive a flange 5 integral with plate 1 and apertured to allow passage of the bolt head 6. A follower 7 operated by knob 15 is mounted on the coverplate, whilst follower-mechanism key-operated by a cylinder lock 16 is mounted on the back plate of case 8. The cylinder case may be affixed by screws 17 and plate 18 as shown, or may form part of, or be secured to, case 8. Holes 13, Fig. 6, are provided in flange 2 for the attachment screws. The key-operated follower-mechanism described comprises a cam 21, Fig. 5, rotated by the lock 16, and a freely mounted member 10 having a pin 22 lying in the path of cam 21. When cam 21 is rotated in one direction it causes a nose 10<a>, of member 10 to bear against the tail-bar 23 of the latch bolt to withdraw the bolt. Rotation in the opposite direction moves pin 22 into engagement with a hook 24, Fig. 6, mounted on the bolt, which is thus dead-locked. When the bolt is held retracted by the usual handoperated stop, not shown, key-operation is prevented by a projection 10<b> on member 10 fouling bar 23 and preventing full rotation of the key. A pair of spaced hooks 24 may be provided to permit reversibility of the bolt. Retraction of the bolt by handle 15 is effected by a plate 70 engaging bar 23 and provided with lug 71 associated with one spring-supporting rod 72, a second spring being mounted on rod 73. The arrangement is such that handle-operation compresses both springs, but key-operation compresses only one spring, plate 70 remaining stationary. Various methods are described of building up the combined case 8 and cover 1. Modifications are described for using cover 1 to hide the attaching screws. Figs. 15, 16 show case 8 with a flange conforming to that of the cover and having recesses 41 through which inturned lugs 42 on the cover may be passed, and engaged by sliding movement of the cover. Fig. 19 shows the cover formed with internal upstanding lugs 48 with recesses engaging projections 46 on case 8 by a sliding movement. In another form the ends of attachment lugs integral with the case are spaced from the face of the door and engaged by inturned lugs on the cover. Another form provides headed studs on the cover engaging key-hole slots in the attachment flange of the case. The invention may be applied to lever-handle locks described in Specification 412,994, or having cylinders arranged as in Specification 397,530.